Automatic safety device for headlight systems



Feb. 29, 1944.

c. D. BRADLEY 2,342fi39 AUTOMATI C SAFETY DEVICE FOR HEADLIGHT SYSTEMS Filed May 8, 1941 2 Sheets-Sheet l mam Feb. 29, 1944 Q Q HA L 2,342,639

AUTOMATIC SAFETY DEVICE FOR HEADLIGHT SYSTEMS Filed May 8, 1.941 2 Sheets-Sheet 2 4 Patented F e. 29, 1944 UNITED STATES PATENT OFFICE amass A auroma'ric sum nnvrca ron naimucn'r srs'rmus Clifford 1). Bradley, Aitkin, Minn. Application May a, 194;, Serial No. 392,461

' -s Claims. (01. 171-97) My present invention relates to headllsht ystems and, generally stated, has for its object the provision of a system that will take care of all of the accidents or contingencies that are likely to occur, by automatically making certain changes or corrections, whereby light will he produced, in one way or another, and there will not be a total failure in the light production.

Especially the invention is applicable to headlights of automobiles or other motor-propelled vehicles wherein both high and low-beam pro Jecting filaments are employed; and in the accompanying drawings I have illustrated the invention as incorporated in such a headlight system. In this improved system the following conditions are taken care of:

1. If the fuse of a low-beam circuit is blown out, the circuit will be completed through the other fuse;

2. If either high-beam filament goes out, the low-beam of the headlight will be automatically cut in, without disturbing the other headlight;

3. If either low-beam filament goes out, the high-beam filament of that headlight will automatically be turned on, without disturbing the other headlight; and if the high-beam of one of the headlights and the low-beam of the other headlight goes out, the circuit of each headlight will be completed through the remaining filament.

4. If either filament of either headlight goes out, control will be taken away from the highbeam selector switch, and this will warn the operator that something is wrong with the system, for the operator can not then cut out either headlight by operating the high-low beam switch; and v 5. If the lead to the low-beam filament is broken, it has the same effect as burning'out of a filament; but if such a lead becomes shorted or grounded, that will result in blowing of a fuse which will produce an open circuit that will be I corrected in the same manner as though a fuse or filament had burned out.

My invention, as applied to the headlight system of an automobile or similar motor-propelled vehicle, is illustrated in the accompanying drawings wherein like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a diagrammatic view showing the system and illustrating the condition that exists when the manual on-and-ofl' or master switch is closed and the high-low beam control switch is also closed;

Fig. 2 is a diagrammatic view illustrating the condition that exists when one of the high-beam filaments of the right hand headlight has been broken or disrupted;

Fig. 3 is a diagrammatic view illustrating the condition that exists when the low-beam filament of the left hand headlight has been broken: and

Fig. 4 illustrates the condition that exists when, for example, the high-beam filament of the left hand headlight and the low-beam filament of the right hand headlight are broken or disrupted.

In the drawings all of the parts are diagrammatically illustrated and in the diagrams certain of the elements are indicated as follows:

The car battery, which is grounded at one side, is-indicated by the character B. The manually operated ofl-and-on or master switch is indicated by the numeral I 0. The left hand headlight II includes a hish beam filament I 2 and a low-beam filament I3, both of which are grounded on one side. The right hand headlight Ila includes a high-beam filament I2a and a lowbeam filament Ila, both of which are grounded on one side.

The numeral I 4 indicates "a balanced electromagnet which may have and preferably does have a single coil that is connected in circuit with the high-beam filaments of both headlights and has an important relation to the electrical resistance and conductivity of the said highbeam filaments, all as will be-hereinafter more fully disclosed.

The numerals I5 and lid indicate fuses which,

through electrical connections and devices hereinafter described. are connected in circuits that lead respectively tothe high-beam. and low-beam filaments of the light bulbs. The numerals l6 and Isa indicate multi-coil relay magnets. The magnet I8 is provided with low resistance working coil I1 and a high resistance holding coil I8; and the magnet IOa islikewiseprovided with a low resistance working coil Ila and a high resistance holding coil m. Relay magnet I8 operates a relay switch Is, and relay m net Ila operates. a relay switch lid. The switches II and its may be assumed to be normally gravity closed. Balanced magnet It operates on switches 20 and 200, both of which may be assumed to be normally closed by gravity.

The numeral 2| indicates the high-low beam control switch. 1 Oif-and-on switch I0 is in a lead I! that extends from one side of the battery to both of the fuses I5 and Ila. High-beam fuse I5,.by a lead 23 that includes high-low'beam switch 2|, is connected to one terminal of the coil of balanced magnet M; and the other terminal of the coil of said magnet I E is connected to the high-beam filaments of both headlights by a divided lead 24. Lead 23 has branches 25 and 250. that are connected respectively to the fixed element of switches I9 and I9a. The movable elements of the switches I9 and I9a, by wire or lead 26, is connected back to lead 23.

Low-beam fuse Ia, by wire or lead 21, is connected to the coils I1 and I8 of relay magnet I6 and to coils Na and I8a of relay magnet I6a. The other terminal of coil II, by a lead 28, is connected to the fixed terminal of switch and the corresponding terminal of coil I'Ia by a lead 28a is connected to the fixed terminal of switch 20a. The holding coil I8 of relay magnet I6 is connected by a wire or lead 29 that is connected to the movable element of switch 20, and the cor responding terminal of holding magnet I8a by a lead 29a that is connected to the movable element of switch 20a.

The movable element of switch 20a, by a lead 30, is connected to the low-beam filament I3 of left hand headlight II; and the movable element of switch 20a by a lead a is connected to the low-beam filament I 3a of right hand headlight Ila.

Before describing the operation of the system under varying conditions, the following facts should be further stated. The coil of the balanced relay I4 has such resistance that when both of the high-beam filaments I2 and I2a are intact, and their circuits closed, sufficient current will run through the coil of said balanced relay to raise and open the switches 20 and 20a, as shown in Fig. l; but the resistance in the coil of said balanced relay is so high that if one of the high-beam filaments is broken, the current will be cut down to such an extent that there will not be suficient energy in magnet I4 to raise the movable elements of switches 20 and 20a and open the said switches.

In respect to the relay magnets I6 and Ilia, there is such low resistance in the operating coils IT and IIa that whenever the current is closed therethrough, the said magnets will exert sufficient energy on the movable elements of switches I9 and I9a to open the said switches; but the resistance in the coils I8 and Mia is so great that closing of the circuits therethrough will not energize the said magnets to an extent suificient to open the said switches, but nevertheless, whenever the circuit is closed through the said holding coils I8 or I8a, there will be sufiicient energy exerted in the respective relay magnets to hold the switches I9 and/or I9a open if the said switches be open at that particular time.

-Fig. 1 shows the condition of the system when the hight and low filaments of both headlights are intact and when the master or cut-in-andout-switch I0 and the high-low beam controlling switch 2| are both closed, and, of course, also when fuses I5 and I511 are intact. Under these conditions the high-beam filaments I2 and I2a will be energized through a pair of parallel. primary high-beam operatingcircuits as follows:

From battery through switch I0, fuse I5, switch I, lead wire 23, the coil of balanced magnet It, lead wires 24 and 25a, through both high-beam filaments I2 and I2a, and to ground. Thus magnet I i, when energized, instantly opens both switches 29 and 20a. 7

When switch ID was first closed, switches l9 and I911, and 20 and 20a were closed, a current was then fiowing through the operating coils IT is and I'm of magnets I6 and I6a as well as through the high resistance holding coils I8 and I 8a so that simultaneously the said switches I9 and Na. 20 and 20a were opened, as shown by full lines in Fig. 1. As a result of these operations not only were switches 20 and 20a opened, but were held open by balanced magnet I4, which cut the circuit through the coils I1 and lid allowing current to flow through the high resistance coils I8 and I8a so that switches I5 and I9a were held open.

Under the conditions just stated, the current will fiow through fuse I5 but not through fuse I5a because the current through the latter which leads to the low-beam filaments I3 and I3a is broken at then open switches 20 and 20a. If fuse I5 should be blown out or disrupted, the current through magnet It will be broken and the latter being de-energized will drop and permit the switches 20 and 20a to automatically close, thereby cutting the high-beam filaments I2 and I2a out of action and closing the circuit through the low-beam filaments I3 and I3a, respectively, through leads 30 and 30a.

If in the first instance it'is desired to cut out the high-beam filaments and cut in the low-beam filaments, then high-low switch 2I should be manually opened. This will, in itself, cut out the circuit through magnet I4 allowing switches 20 and 20a to automatically close and then the current will fiow from battery through fuse I5a, leads 21, coils I1 and I'Ia, leads 28 and 28a, switches 20 and 20a, and leads 30 and 30a to the lowbeam filaments and to ground. This last noted action is substantially the same as that which takes place when fuse I5 is burned out or disrupted.

If, while the system is set as above described for low-beam filaments, fuse I 5a should burn out or be disrupted, that would break the circuit through the coils I1 and Na, I8 and I8a, causing switches I9 and I9a to automatically close and that would allow the current to fiow from battery through high-beam fuse I5, leads 25 and 25a, switches I9 and I 9a, leads 26 and 23, magnet I 4, lead 24 and high-beam filaments I2 and I2a and to ground.

In this system the burning out of one or the other of the high-beam filaments I2 and Ma has the same or substantially the same effect as burning out of the high-beam fuse I5. In either event the described action is produced by breaking of the circuit between the battery and the respective high-beam filaments. Short-circuiting of any of the connections described would result in burning out of a fuse with the results above described.

Fig. 2 illustrates the condition that would prevail if one of the high-beam filaments, to wit: as shown, the high-beam filament I2a of the right hand headlight, should be disrupted while the switches II) and 2i are closed, and here it will be noted that the current then fiows through fuse I5a, coils I7 and I8, Na and Ida, through switches 20 and 28a, and through both of the low-beam filaments I3 and I3a.' Under the conditions shown in Fig. 2, the magnet I l is de-energized to such an extent that it will not hold switches 20 and 20a open, since at that time the current to said magnet It must fiow entirely through the one high-beam filament and, as already stated, would be reduced to such an extent that it loses its hold on the switches 20 and 20a and permits the same to automatically close. Under the conditions above described in respect to Fig. 2, and

when both switches III and 2| are closed, the disruption oi the high-beam filament oi the right hand headlight I la will cause the current to fiow through the low-beam filament'of both headlights and also through the high-beam filament oi the left hand headlight u. n, at this time, the switch 2I should be open, then the current will ilow only through the low-beam filaments of both headlights. Under the conditions illustrated in Fig. 2, the current will fiow through the wires or leads indicated by full lines, while the wires indicated by dotted lines are dead wires or leads.

Fig. 3 shows a condition that prevails when one of the low-beam filainents is burned out or disrupted while switch III is closed and switch 2I is opened. When one oi the low-beams, to'wit: as shown, the low-beam filament oi the left hand headlight II is disrupted, and at which time the curtrzgt will fiow through high-beam fuse I5, swi I 9, magnet I4, and high-beam filaments of both light bulbs.

At this point attention is called to the fact that switch I9 is then automatically closed because the burning out or disrupting or the current through the one low-beam filament broke the circuit through both coils of magnets I B and entirely de-energized the same.

11', instead of low-beam filament of the left hand headlight, the low-beam filament of the right'hand headlight burned out, then substantially the same action would'take place, except that the current would then be cut oil from both coils of magnet Ilia and it would be switch Ila instead of switch I9 that closed to perform the above operation.

Under the conditions illustrated in Fig. 3 the current win fiow through the wires or leads in dicated by full lines, while the wires indicated by dotted lines are dead wires or leads.

Fig. 4 illustrates a condition that exists in the system if and when the low-beam filament of one headlight and the high-beam fil'ament of the other headlight are at the same time disrupted. The action produced under the conditions illus trated in Fig. 4 is quite similar to that illustrated in Fig. 2, except that the current through both coils IIa and Ida of magnet "la is broken causing m'agnet Iia to be de-energized and switch Isa to close. Under the conditions illustrated in Fig. 4 the current will flow through the wires or leads indicated by full lines, while the wires indicated by dotted lines are dead wires or leads.

The above application is filed as a continuation-in-part oi. my co-pending application filed July 22, 1940, under Serial No. 346,881 and entitled "Automatic safety device for headlight systems."

Certain terms used in the claims hereof may be applied to the disclosure of this application as follows, to wit:

a. There are, in the preferred form illustrated,

' a pair of primary high-beam filament operating circuits. each serving a difierent one of the high beam filament I2 and I2a. The primary operating circuit of this parallel pair of circuits which.

serves to energize the high-beam filament I2 comprises switch I0, lead 22, fuse I5, lead 23, including switch 2I, the coil of balanced relay I4,'and lead 24; and the other of said primary high-beam filament operatiing circuits, and which serves to energize the high-beam filament I2a, comprises switch I0, lead 22, i'use I5, lead 23, including switch 2|, the coil oi balanced relay II, part of lead 24, and a lead 24a. of course, bothoi this parallel pair or primary high-beam filament operating circuits are completed from their respective filaments back to the battery through ground.

These parallel circuits are shown as complete and operative in Fig. 1.

b. There are, in the preferred form illustrated, two pairs of parallel secondary operating circuits for the high-beam filaments and each circuit of each 01' these pairs of circuits is adapted to operate a difi'erent one or the high-beam filaments. One of these pairs of parallel secondary highbeam operating circuits comprises switch I0, lead 22, fuse I5, part of lead 2!, lead 25, the contacts of relay switch I9, part of lead 26, the upper part of lead 23, the coil of balanced relay I 4, lead 24, and a branch lead 24a. The above described pair of secondary high-beam filament operating circuits is shown as being complete and operative by full lines in Fig. 3. The other of these pairs of parallel secondary high-beam operating circuits comprises switch I II, lead 22, iuse I 5, a short part of lead 23, lead 25a, the contacts or relay switch I9a, all or lead 26, the upper part of lead 23, the coil of balanced relay I4, lead 24, and a branch lead 24a. One 01' the last described pair of parallel secondary high-beam filament operating circuits is shown as being complete and operative in Fig. 4, while the other thereof is shown as being broken and inoperative by virtue of open contacts of switch I9 in Fig. 4.

What I claim is:

1. In a vehicle headlight system, two electrical- 1y operated light filaments, primary and secondary operating circuits for on or said light filaments, an operating circuit for the other of said light filaments, a holding circuit also including said other light filament but providing insufficient energy to illuminate the same, a manually controlled oil-on switch common to all of said circuits, a manually operated filament selector switch interposed in the said primary operating circuit, automatic switch means responsive to energization of the said other light filament operating circuit to open the said secondary circuit and responsive to energization of the said holding circuit to retain said secondary circuit open independently of energization of the operating circuit or the said other light filament and responsive to coincidental de-energization of said holding circuit and said other light filament operating circuit to close said secondary operating circuit, and automatic switch means responsive to energization of either of said primary or secondary operating'circuits to open the operating cir-' cuit or the said other light filament and responsive to coincidental de-energization or said priage drop across said low-beam filament to cause operation of the same, a manually controlled oil'- on switch common to all or said circuits. a manuall operated high-low beam selector switch interposed in the primary high-beam filament circuit, automatic switch means responsive to energization oi the low-beam filamentoperating circuit to open the secondary high-beam filament circuit and responsive to energization of the said holding circuit to retain said secondary highbeam filament circuit open independently of energi'zation of the low-beam filament operating circuit and responsive to coincidental de-energization of said holding circuit and said low-beam filament operating circuit to close said secondary high-beam filament operating circuit, and automatic switch means responsive to energization of either said primary or secondary high-beam filament operating circuits to open the low-beam filament Operating circuit and responsive to coincidental de-energization of said primary and secondary high-beam filament operating circuits to close the low-beam filament operating circuit.

3. The structure defined in claim 1 in which there are two headlights, each headlight having two of the said electrically operated light filaments, the corresponding filaments of the two headlights being connected in parallel.

4. The structure defined in claim 2 in which there are two headlights, each provided with the said high-low beam filaments, the corresponding filaments being electrically connected in parallel.

5. The combination with a, vehicle head lamp having high and low-beam filaments, primary and secondary operating circuits for the highbeam filament, an operating circuitfor the lowbeam filament, a manual high-low beam selector switch interposed in the primary high-beam filament circuit, an electro-magnetically opened relay switch having it switch contacts interposed in the low-beam filament circuit and its switch operating winding connected in series with the primary and secondary high-beam filament operating circuits so that said relay switch contacts will be opened when the said high-beam filament is energized through either of its said primary or secondary circuits, and an electro-magnetically opened relay switch having its switch contacts interposed in the said secondary high-beam circuit and its operating coil connected in series with said low-beam filament circuit, and a high resistance holding circuit for the last said relay switch and which includes said low-beam filament but independent of all of saidswitch contacts.

6. The combination with a vehicle head lamp having high and low-beam filaments, primary and secondary operating circuits for the high-. beamfilament, an operating circuit for the lowbeam filament, a'manual high-low beam selector switch interposed in the primary high-beam filament circuit for opening and closing the same, an electro-magnetically opened relay switch having its switch contacts interposed in the lowbeam filament circuit and its switch operating winding connected in series with the primary and secondary high-beam filament operating circuits so that said relay switch contacts will be opened when the said high-beam filament is energized through either of its said primary or secondary circuits, and an electro-magnetically opened relay switch having its switch contacts interposed in the said secondary high-beam circuit and its operating coil connected in series with said low-beam filament circuit, and a high resistance holding circuit for the said relay switch and which includes said low-beam filament but is independent of all of said switch contacts, said high resistance holding circuit DIOVidil'lg insuihcient energy to illuminate the said filament in circuit-therewith.

7. The ,combination with a vehicle head lamp having high and low-beam filaments, primary and secondary operating circuits for the highbeam filament, an operating circuit for the lowbeam filament, a manual high-low beam selector switch interposed in the primary high-beam filament circuit for opening and closing the same, an electro-magnetically opened relay switch having its switch contacts interposed in the lowbeam filament circuit and its switch operating winding connected in series with the primary and secondary high-beam filament operatingcircuits so that said relay switch contacts will be opened when the said high-beam filament is energized through either of its said primary or secondary circuits, and an electro-magnetically opened relay switch having its switch contacts inter; posed in the said secondary high-beam circuit and its operating coil connected in series with said low-beam filament circuit, and a high re sistance holding circuit for the last said-relay switch and which includes said low-beam filament but is independent of all of said switch contacts, said high resistance holding circuit providing insufiicient energy to illuminate the said filament in circuit therewith, and a master control switch common to all of said circuits. V v

8. The combination with a pair of vehicle head lamps each having a high beam filament and a low beam filament, parallel primary operating circuits for the high beam filaments of said head lamps, two pairs of parallel secondary operating circuits for the high beam filaments of said head lamps, parallel operating circuits for the low. beam filaments of said head lamps, a manual high-low beam selector switch interposed serially in and common to the parallel primary high beam filament operating circuits and adapted to open and close the same, an electromagnetically opened balanced relay switch mechanism involving separate pairs of cooperatin contacts each interposed in a difierent of said parallel low beam filament operating circuits and having its switch operating winding connected serially in and common to both pairs of primary and secondary operating circuits of both high beam filaments, the said winding of the said balanced relay switch being so proportioned that the said cooperating pairs of contacts thereof will be opened when both high beam filaments are energized through both parallel primary circuits or both pairs of secondary circuits but will be de-energized sufilciently to permit closing of its cooperating pairs of contacts when either one or both of the'high beamfilaments are de-energized, a like pair of electro-magnetically opened relay switches each having a pair of contacts interposed in and common to a difierent parallel pair of secondary high beam filament operating circuits and an operating coil connected in series with a difirent parallel pair of low beam filament operating circuits, and a high resistance holding winding connected in parallel with its operating winding but in shunt with the balanced relay contacts of the low beam filament circuit common to the operating winding of that relay, said high resistance holding windings passing insufilcientenergy to illuminate the filament in circuit therewith, and a master control switch common to all of said circuits.

CLIFFORD D.' BRADLEY. 

